Abstract

The Leduc reefs of central Alberta are surrounded by the Ireton shales. In this stratigraphic interval, differential compaction has induced structure in the overlying formations. We have analyzed the structural deformation of the strata above the Wizard Lake reef. In this area Lower Cretaceous rocks lie unconformably on Upper Devonian strata. Removal of the upper Paleozoic beds has resulted in the loss of part of the compaction record. A quantitative study of the change of structure with depth allows us to estimate the maximum thickness of sediment eroded. For the Wizard Lake area we find that this is about 1750 feet. Reconstruction of a regional cross-section indicates this to be a reasonable value.